Alternately, open descr_regions, copy into a word processor, then do a search and highlight on "slaves", that should reveal the exact number of regions as well. I've used a similar method for counting buildings in EDB. Search for "plugins" or "levels" to count the trees, and "upgrades" for the number of building levels.
Veni, Vidi, well... you know.
Extended Cultures, A modification of RTW.
Si hoc legere posses, Latinam linguam scis.
ɪf ju kæn ɹid ðɪs, ju noʊ liŋgwɪstɪks.